JP2003284264A - Contactless power feeding system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contactless power feeding system with a simple structure capable of identifying the conditions of a power receiving side for power supply control. <P>SOLUTION: This contactless power feeding system 1 generates induced voltage to a second coil L2 by magnetic flux generated by a first coil L1 in which a high frequent power is supplied from a high frequent inverter circuit 11, and converts the induced voltage into a prescribed form by a power converting circuit 21 to output it to a load 30. A signal generating device 24 generates a signal having a frequency of a harmonic element in an oscillation frequency of the high frequent inverter circuit 11, and a signal receiving circuit 12 outputs a signal for detecting the presence of a contactless power receiving device 2 and a signal for detecting a signal generated by the signal generating device 24. An inverter control circuit 13 controls the oscillation of the high frequent inverter circuit 11 based on the detected signals. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a contactless power feeding system.

[0002]

2. Description of the Related Art In recent years, non-contact power transmission technology has been widely used in portable electronic equipment, electric vehicles, industrial equipment and the like. This technology is especially useful for products used around water such as electric toothbrushes and electric shavers. In a contactless power supply system in which a power supply side (power supply side) and a load side (power reception side) are detachably used, when power is supplied from the power supply side to the load side by electromagnetic induction, the power is supplied when the load side is removed. It is necessary to stop the oscillation of the oscillation switching element used in the supply side inverter circuit or reduce the oscillation intensity. The reason for this is that if oscillation is continued when there is no load, energy is wasted due to power loss on the power supply side.In addition, if metallic foreign matter other than the correct load is placed, induction heating will occur. By the action
This is because the metal overheats abnormally and is dangerous. further,
When the load is a secondary battery or the like, it is necessary to perform charge control when the secondary battery is fully charged.

That is, for non-contact power transmission, "oscillation stop or suppression control for energy saving control and measures against overheating of metal foreign matter when the power supply side is independent" and "continuous power feeding control when a correct load is mounted" , And "electric power transfer control based on the request from the load side" are required.

[0004]

Several conventional examples have been proposed which satisfy all or part of the above three controls. For example, there is a technique disclosed in Japanese Patent Laid-Open No. 6-311658. This is a pair of independent signal coils,
A pair of power coils on the power supply side and the load side are separately provided, and when the load is mounted, power is transmitted to the load by the induction of the pair of power coils. Then, the electric power is used to drive the control circuit on the load side, the control signal is returned from the load side to the electric power supply side by the pair of signal coils, and the electric power supply side controls the oscillation operation based on this control signal. To do.

However, this configuration requires a separate circuit for load detection and oscillation control, and it is necessary to increase the signal frequency in order to easily distinguish the signal frequency from the frequency for power transmission / reception. As a result, there is a drawback that the signal generating circuit becomes complicated, and the noise and the like are strengthened to increase the size and cost.

Further, Japanese Laid-Open Patent Publication No. 11-178249 utilizes the characteristics of self-excited oscillation and takes out a positive feedback loop from the inside of the power supply side to the load side and then back to the power supply side.
This is a circuit that can detect a load with an extremely simple circuit that uses the feedback loop for load information, and that can save power and prevent overheating of metal foreign matter.
Furthermore, since the same power frequency and signal frequency can be used, contactless power transfer can be performed with a simple configuration. However, since the control signal is a positive feedback feedback signal having the same frequency as the power frequency, amplification control of the signal amplitude cannot be performed, and it is difficult to secure a noise margin.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a contactless power feeding system having a simple structure capable of controlling the power supply by identifying the situation of the power receiving side. To provide.

[0008]

According to a first aspect of the present invention, there is provided a high frequency inverter circuit for outputting high frequency power, an inverter control circuit for controlling the high frequency inverter circuit, and high frequency power supplied from the high frequency inverter circuit. A contactless power supply including a first coil for supplying power by coupling and a signal receiving circuit having an input signal coil, and the inverter control circuit controlling the high-frequency inverter circuit based on a signal detected by the input signal coil. Device,
A second coil, which is arranged to face the first coil and receives power by magnetic coupling, a power conversion circuit for converting the output of the second coil into a predetermined electric energy, and an oscillation frequency of the high frequency inverter circuit. A signal generator that generates a signal having a frequency of a harmonic component, a secondary-side control circuit that controls a signal generated by the signal generator, and a load that is supplied with electric energy from the power conversion circuit. A contact power receiving device, and the first coil and the second coil have a transformer structure in which the first coil and the second coil are detachable from each other,
The input signal coil outputs a signal that detects the presence or absence of the non-contact power receiving device and a signal that detects a signal generated by the signal generating device.

According to a second aspect of the present invention, in the first aspect, the signal generating device is a resonance circuit including a third coil and a capacitor, and having a resonance frequency of a frequency of the higher harmonic component. When the non-contact power receiving device is generally arranged opposite to the contact power feeding device, it is extracted from the magnetic field, magnetic flux in the non-contact power feeding device and the non-contact power receiving device, or the voltage or current information in the non-contact power receiving device. A signal of the frequency of the harmonic component is generated, the input signal coil detects the signal of the frequency of the harmonic component, and the inverter control circuit operates the high frequency inverter circuit based on the signal detected by the input signal coil. The control is performed to control power feeding from the non-contact power feeding device to the non-contact power receiving device.

According to a third aspect of the present invention, in the first or second aspect, the frequency of the harmonic component is a frequency of the harmonic component that is an odd multiple of the oscillation frequency of the high frequency inverter circuit.

According to a fourth aspect of the present invention, in the third aspect, the odd multiple harmonic component is a third harmonic component.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the power conversion circuit includes a circuit for half-wave rectifying the output of the second coil.

According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the signal receiving circuit includes a resonance capacitor connected to the input signal coil, and resonates at a frequency of the harmonic component. To do.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the input signal coil is a fourth differentially connected type.
And a fifth coil.

According to an eighth aspect of the present invention, in any one of the first to seventh aspects, in the case where the non-contact power receiving device is generally opposed to the non-contact power feeding device and the non-contact power receiving device requests power feeding. The output of the signal generator is increased.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, in the case where the non-contact power receiving device is generally opposed to the non-contact power feeding device and the non-contact power receiving device rejects power feeding. The secondary side control circuit reduces the output of the signal generator.

According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the high frequency inverter circuit performs intermittent oscillation when the non-contact power feeding device is present alone.

According to an eleventh aspect of the present invention, in the high frequency inverter circuit according to any one of the second to tenth aspects, a switching element for oscillation and a switching element for self-excited control for connecting a control end of the oscillation switching element to a ground level. And performing a self-excited oscillation, wherein the inverter control circuit intermittently stops the oscillation of the self-excitation control switching element to intermittently stop the oscillation operation of the oscillation switching element, and the forced stop circuit, An oscillation switching switching element that stops the intermittent stop operation of the forced stop circuit by turning on at the output of the input signal coil, and when the non-contact power supply device is independent, the output voltage of the input signal coil is The switching element for oscillation switching is maintained at a voltage at which it is turned off, and the forced stop circuit operates to cause the oscillation switch for oscillation. When the oscillation operation of the contacting element is controlled to intermittent oscillation, the non-contact power receiving device is generally arranged in opposition to the non-contact power feeding device, and when the non-contact power receiving device requests power feeding, the signal generating device is the The magnetic field and magnetic flux in the non-contact power feeding device and the non-contact power receiving device, which are generated during the period in which the oscillation operation of the oscillation switching element is intermittent oscillation.
Alternatively, the third coil is excited by a signal of the frequency of the harmonic component extracted from the voltage or current information in the non-contact power receiving device, and the third coil is roughly arranged to face the third coil.
The output voltage of the input signal coil for detecting the magnetic flux generated in the third coil becomes a voltage at which the oscillation switching switching element is turned on, and the forced stop circuit stops the operation to oscillate the oscillation switching element. When the operation is controlled to continuous oscillation, the non-contact power receiving device is generally arranged in opposition to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator is configured to suppress the harmonic component. The frequency signal is reduced to suppress the excitation of the third coil, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to cause the oscillation. It is characterized in that the oscillation operation of the switching element is controlled to intermittent oscillation.

According to a twelfth aspect of the present invention, in any one of the second to eleventh aspects, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of a resonance circuit including a third coil and a capacitor. When the non-contact power receiving device is generally arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element. Changing at least one of the frequency, the amplitude and the waveform of the signal generated by the resonance circuit of the signal generator with respect to the frequency, the amplitude and the waveform when the power supply is required,
The input signal coil detects a signal generated by the signal generator, the inverter control circuit controls the high frequency inverter circuit based on the signal detected by the input signal coil, and causes the non-contact power feeding device to operate the non-contact power supply device. The feature is that power supply to the contact power receiving device is reduced.

According to a thirteenth aspect of the present invention, in any one of the second to eleventh aspects, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generating device, When the non-contact power receiving device is generally arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element to operate the signal. At least one of the frequency, the amplitude, and the waveform of the signal generated by the resonance circuit of the generator is changed with respect to the frequency, the amplitude, and the waveform when the power supply is required, and the input signal coil causes the signal generator to change. Is detected, the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil to perform the contactless power feeding. Non-contact power supply system in accordance with claim 2 to 11, wherein the reducing the power supply to put al the contactless power receiving apparatus.

According to a fourteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device short-circuits or opens the auxiliary coil in which at least a part of the magnetic flux generated by the first coil links with the auxiliary coil. An auxiliary switching element, the non-contact power receiving device is generally arranged opposite to the non-contact power feeding device, and when the non-contact power receiving device rejects power feeding, the secondary side control circuit is configured to perform the auxiliary switching. It is characterized in that the element is operated to reduce at least one of the frequency and the amplitude of the signal generated by the resonance circuit of the signal generator with respect to the frequency and the amplitude when the power supply is required.

According to a fifteenth aspect of the present invention, in the twelfth aspect, the signal generator comprises a resonance circuit in which a third coil and a capacitor are connected in parallel, and a diode and an auxiliary switching element are provided between both ends of the parallel circuit. When the non-contact power receiving device is arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit controls the auxiliary switching element. It is characterized in that it is turned on to suppress the excitation of the third coil.

According to a sixteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, and the non-contact power feeding device is provided with the non-contact power receiving device. , The secondary side control circuit operates the auxiliary switching element when the contactless power receiving device is arranged to face each other and rejects power supply,
The frequency of the signal generated by the resonant circuit of the signal generator,
It is characterized in that at least one of the amplitudes is made smaller than the frequency and the amplitude when the power supply is required.

The invention of claim 17 is based on claims 12 to 16.
In any one of the above, the auxiliary switching element is an element that conducts in one direction.

The invention of claim 18 is the invention of claims 12 to 17.
In any one of the above, a capacitor connected in series with the auxiliary switching element is provided.

The invention of claim 19 is based on claims 12 to 17.
In any one of the above, a capacitor connected in parallel to the auxiliary switching element is provided.

The invention of claim 20 is characterized in that in any one of claims 1 to 19, the magnetic coupling between the second coil and the third coil is loose coupling.

According to a twenty-first aspect of the present invention, in any one of the first to twentieth aspects, the output section of the input signal coil is provided with a filter for detecting the same frequency band as the frequency of the harmonic component. .

The invention of claim 22 is characterized in that, in any one of claims 1 to 21, the high-frequency inverter circuit applies a sinusoidal alternating voltage across the first coil.

In a twenty-third aspect of the present invention according to any one of the first to twenty-second aspects, the high frequency inverter circuit includes an oscillation switching element and a resonance capacitor connected in parallel with the oscillation switching element or the first coil. It is characterized by a single voltage resonant inverter.

According to a twenty-fourth aspect of the present invention, in any one of the seventh to twenty-third aspects, the magnetic coupling between the differentially connected fourth and fifth coils forming the input signal coil and the first coil is loose coupling. And the degree of magnetic coupling between any one of the fourth coil and the fifth coil and the third coil is the same as that between the other of the fourth coil and the fifth coil and the third coil. Is larger than the magnetic coupling degree of.

According to a twenty-fifth aspect of the present invention, in the twenty-fourth aspect, the fourth and fifth coils are arranged symmetrically with respect to the first coil, and the third coil includes the fourth coil and the fifth coil. It is characterized in that it is arranged so as to face either one of the coils.

The invention of claim 26 is based on claim 1,
When power is being supplied from the non-contact power feeding device to the non-contact power receiving device, the voltage across the second coil and the coil current have distorted waveforms, and the signal generating device causes the voltage across the second coil and the coil It is characterized in that it generates a signal whose source is a harmonic component contained in the current.

A twenty-seventh aspect of the present invention is the apparatus according to the twenty-sixth aspect, wherein the input signal coils are differentially connected,
The magnetic coupling between the fifth coil and the first coil is loose coupling, and the degree of magnetic coupling between any one of the fourth coil and the fifth coil and the second coil is the fourth coil. And the fifth
Is larger than the degree of magnetic coupling between the other coil and the second coil.

A twenty-eighth aspect of the present invention is the signal generating device according to any one of the first to twenty-seventh aspects, wherein the signal generating means is a resonance circuit of a third coil and a capacitor having a resonance frequency of the frequency of the harmonic component. And a signal generating means for generating a signal having a harmonic component included in the coil current and a voltage across the second coil as a generation source.

The invention of claim 29 is based on claims 1 to 25,
28. In any one of the 28, the signal generation device includes an inductor connected in series to the third coil.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows a block diagram of a non-contact power feeding system of this embodiment. The non-contact power supply system includes a non-contact power supply device 1 that supplies electric power and a non-contact power receiving device 2 that includes a load to which power is supplied. The non-contact power supply device 1 outputs a high-frequency inverter circuit 11 that outputs high-frequency power. , An inverter control circuit 13 for controlling the high-frequency inverter circuit 11, a first coil L1 which is supplied with high-frequency power from the high-frequency inverter circuit 11 and supplies power by magnetic coupling, and is connected in series with their polarities opposite to each other. The input signal coil Ls including the fourth coil L4 and the fifth coil L5, and both ends of the differential connection circuit for amplifying the output of the differential connection circuit of the fourth coil L4 and the fifth coil L5. A signal receiving circuit 1 including a resonance capacitor C4 connected in between, and the fourth coil L4, the fifth coil L5, and the resonance capacitor C4 operate as a differential resonance circuit. Constitute a.

The non-contact power receiving device 2 has a load 30, and is provided with a second coil L2 arranged to face the first coil L1 to receive power by magnetic coupling and an output of the second coil L2. A power conversion circuit 21 for converting into an output suitable for being supplied to 30; a third coil L3 arranged to face the input signal coil Ls of the signal receiving circuit 12;
Resonant capacitor C8 connected across coil L3
And a switch S connected across the resonance capacitor C5.
2 and a secondary-side control circuit 23 that outputs a signal for controlling ON / OFF of the switch S2, and the resonance circuit of the third coil L3 and the resonance capacitor C8 outputs the signal from the non-contact power receiving device 2. The signal generating device 24 is configured.

The contactless power feeding system as described above is the first
The coil L1 and the second coil L2 have a transformer structure in which they can be detached and attached freely, and the magnetic flux generated by the first coil L1 supplied with the high frequency power from the high frequency inverter circuit 11 causes the second coil L2 to move. Generates an induced voltage, converts the induced voltage into a predetermined form by the power conversion circuit 21, and outputs it to the load 30. Then, the signal generator 24 generates a signal having the same frequency as the harmonic of the oscillation frequency of the high frequency inverter circuit 11, and the input signal coil L
s detects this signal, and the inverter control circuit 13 controls the oscillation of the high frequency inverter circuit 11 based on this detection signal.

Here, the first coil L1 and the input signal coil Ls are arranged so as to be magnetically loosely coupled, and the fourth coil L4 and the fifth coil L5 are also magnetically loosely coupled. Are arranged as follows. And the fourth on the primary side
Facing the coil L4 of the third coil L3 on the secondary side.
Are arranged. Magnetically loosely coupled means that all of the magnetic flux created by one coil does not interlink with the other coil.Even if the magnetic core is on the coil axis, each coil is completely If they are placed in close contact with each other and separated from each other in the axial direction or the radial direction without overlapping, loose coupling will occur.

Next, the configuration of each part will be described in detail using the specific circuit configuration shown in FIG. First, the high frequency inverter circuit 11 of the contactless power supply device 1 is a self-excited oscillation circuit, and includes a series circuit of a resistor R2 and a capacitor C1 connected in parallel to a series circuit of a DC power source E1 and a switch S1, and a resonance capacitor C2. Switching element F for oscillation
A series circuit of ET1 and a resistor R1 is provided, and a first coil L1 is connected in parallel to the resonance capacitor C2.
A feedback coil L6, which is tightly coupled with the first coil with the illustrated polarity, is connected between the connection midpoint between the resistor R2 and the capacitor C1 and the gate of the switching element FET1. The self-excited oscillation control switching element Tr1 connected in parallel to the capacitor C1 via the feedback coil L6 is an element that controls the oscillation of the switching element FET1. A resistor R3 is connected between the source of the switching element FET1 and the base of the switching element Tr1, and a capacitor C is connected between the base and the emitter of the switching element Tr1.
3 is connected.

The configuration of the signal receiving circuit 12 is the same as that of FIG. 1, and one output terminal is connected to the ground of the high frequency inverter circuit (the low voltage output side of the DC power source E1).

The inverter control circuit 13 is a switching element Tr for controlling self-excited oscillation of the high frequency inverter circuit 11.
1 is turned on / off to control the oscillation of the high frequency inverter circuit 11 in two ways, continuous oscillation and intermittent oscillation, and the diode D3 and the zener whose one end is connected to the other output end of the signal receiving circuit 12 The other end of the series circuit of the diode ZD1 and the resistor R7 has a switching element Tr for switching oscillation.
It is connected to the base of 2. A capacitor C5 is connected between the output ends of the signal receiving circuit 12 via a diode D3, and a resistor R8 is connected between the base and emitter of the switching element Tr2. The drain of the switching element FET1 is connected to the ground level via the series circuit of the resistors R4 and R5, and the capacitor C6 is connected in parallel to the resistor R5 via the diode D2. The midpoint of the connection between the diode D2 and the capacitor C6 is the diode D1.
And a resistor R3 to connect to the base of the switching element Tr1 for self-oscillation control, and further to a collector of the transistor Tr2 via a resistor R6. Here, the resistors R4 and R5, the diodes D1 and D2, and the capacitor C6 form a forced stop circuit 15 that intermittently stops the oscillation operation of the switching element FET1.

The secondary circuit 21 of the non-contact power receiving device 2 has a capacitor C7 connected between the output terminals of the second coil L2.
And a rectifying diode D4 connected in series to one output end of the second coil L2, and the output obtained by half-wave rectifying the induced voltage of the second coil L2 is a secondary battery 22 as a load.
, And both ends of the secondary battery 22 are connected to the secondary side control circuit 23.

A resonance capacitor C8, a series circuit of a diode D5 and an auxiliary switching element Tr3 are connected between both ends of the third coil L3, and a base of the auxiliary switching element Tr3 is connected to the secondary side control circuit 23. ing.

Next, the process from the start of oscillation from the time when the switch S1 is turned on to the continuous oscillation will be described with reference to the waveform diagram shown in FIG. First, when the switch S1 is turned on, the DC power source E1 that generates the voltage Ve1 charges the capacitor C1 via the resistor R2. At this time, no induced voltage is generated in the feedback coil L6 that is tightly coupled to the first coil L1, so that the gate voltage Vg of the switching element FET1 is equal to the voltage Vc1 of the capacitor C1. The gate voltage Vg gradually rises, and the switching element FET
When the voltage Vgon at which 1 can be turned on is reached, the switching element FET1 is turned on, and the drain voltage Vd becomes almost zero potential. At this time, the resonance voltage Vc2 across the resonance capacitor C2 connected in parallel with the first coil L1 is charged with the power supply voltage Ve1 of the DC power supply E1, and the first coil L1 has a substantially monotonically increasing coil current. IL1 begins to flow.

When the coil current IL1 starts to flow, an induced voltage is generated in the second coil L2 by the action of the transformer. Similarly, the induced voltage Vf1 is also generated in the feedback coil L6 that is tightly coupled to the first coil L1. Then, the gate voltage Vg seen from the ground level is Vc1 + Vf1.
Then, the switching element FET1 rapidly becomes a stable ON state.

The coil current IL1 is the drain current Id flowing through the resistor R1 through the switching element FET1.
And the voltage Vtr1 of the resistor R1 increases with time. When the voltage Vtr1 reaches a voltage at which the switching element Tr1 can be turned on, the switching element Tr1
Starts to turn on. When the switching element Tr1 starts to turn on, the gate input capacitance of the switching element FET1 and the charge accumulated in the capacitance of the capacitor C1 via the feedback coil L6 start to be extracted, and the voltage Vc1 and the gate voltage Vg start to decrease. When the decrease of the gate voltage Vg progresses, the switching element FET1 starts to shift to the off state, the on-resistance increases, and the drain voltage Vd gradually increases.

As the drain voltage Vd increases, the resonance voltage Vc2 also begins to decrease, and the induced voltage Vf1 of the feedback coil L6 also begins to decrease, so that the gate voltage Vg further accelerates and decreases. As a result, the switching element F rapidly
ET1 shifts to the off state, the voltage Vtr1 also decreases, and the switching element Tr1 turns off again.

The resonance voltage Vc2 is the resonance capacitor C
Due to the resonance action of 2 and the first coil L1, a sinusoidal voltage is obtained, and the coil current IL1 is also sinusoidal. During this period, the capacitor C1 is connected from the DC power source E1 via the resistor R2.
The charging current to V is constantly flowing, and the voltage Vc1 is increased again.

When the resonance voltage Vc2 approaches the end of one cycle, the drain voltage Vd approaches the ground level,
Electromotive force Vf1 and voltage Vc1 of feedback coil L6 at that time
The sum of the gate voltage Vg of
Turn on T1. After that, the oscillation is continued by repeating the above operation. This series of operations is performed by the non-contact power receiving device 2
Is not opposed to the contactless power supply device 1, that is, even when the contactless power supply device 1 is alone, the same operation is performed except that no electromotive force is generated in the second coil.

However, when the non-contact power feeding device 1 is independent, it is necessary to stop or suppress the oscillation of the high frequency inverter circuit 11 in order to save energy and protect the metallic foreign matter from overheating. In the present embodiment, the oscillation of the high frequency inverter circuit 11 is intermittently oscillated by the forced stop circuit 15 to fulfill this role.

The control of the intermittent oscillation operation will be described below with reference to the waveform charts of the respective parts shown in FIG. First, switch S1
The procedure is the same as that described with reference to FIG. The inverter control circuit 13 in FIG. 2 has an integrating circuit that divides the drain voltage Vd by resistors R4 and R5 and accumulates electric charges in the capacitor C6 via the diode D2. The voltage of the capacitor C6 passes through the diode D1 and the base resistance R3 of the transistor Tr1.
When the voltage of the capacitor C6 exceeds the sum of the input voltage value capable of turning on the switching element Tr1 and each voltage drop of the diode D1 and the resistor R3, the switching element Tr1 is turned on.

When the switching element Tr1 is turned on, the charge accumulated in the gate input capacitance of the switching element FET1 and the capacitance of the capacitor C1 via the feedback coil L6 is extracted. At this time, switching element Tr
If the ON time of 1 is maintained for a long time, the voltage Vc1 becomes lower than the voltage in the steady oscillation state, and the voltage recovery by the charging current flowing from the DC power source E1 to the capacitor C1 via the resistor R2 is the steady state voltage. Therefore, the switching element FET1 remains in the off state.

Therefore, the next oscillation start is not performed until the voltage Vc1 due to only the charging current flowing from the DC power source E1 to the capacitor C1 via the resistor R2 reaches the input voltage at which the switching element FET1 can be turned on. That is, a stable intermittent oscillation is obtained by repeating this operation.

What is important for this intermittent oscillation is that it must have a function of first oscillating the high frequency inverter circuit 11 and then delaying it and stopping it. The reason is the high frequency inverter circuit 11
This is because if the switching element Tr1 is turned on before oscillates, the oscillation is permanently stopped. The oscillation stopped state in the circuit of FIG. 2 is the drain voltage Vd.
Since the potential of the resistor R4 becomes the power supply voltage Ve1, the voltage division ratio of the resistors R4 and R5 becomes
It is necessary to set 1 to a value that does not turn on. Then, in order to reach a level at which the switching element Tr1 can be turned on after the oscillation starts, the capacitor C6 is gradually charged using the voltage when the drain voltage Vd becomes higher than the power supply voltage Ve1 due to the oscillation. Then, the voltage division ratio of the resistors R4 and R5 may be set so that the switching element Tr1 can be turned on after an appropriate time has elapsed.
With the above configuration, the high frequency inverter circuit 11 and the inverter control circuit 13 shown in FIG. 2 can perform intermittent oscillation when the contactless power supply device 1 is independent.

By the way, when the non-contact power receiving device 2 is generally arranged so as to face the non-contact power feeding device 1 and power transmission is required, a function of surely stopping this intermittent oscillation is required. In order to surely stop the intermittent oscillation, that is, to perform the continuous oscillation, it is necessary to have a function of judging whether or not the load is correct from the perspective of the non-contact power feeding apparatus 1. In order to make this reliable judgment, A method of sending a predetermined signal from the non-contact power receiving device 2 to the non-contact power feeding device 1 is conceivable. Therefore, the non-contact power receiving device 2 side requires a signal generator 24 using a harmonic resonance circuit. Hereinafter, this operation will be described.

In the contactless power feeder 1, the resonance capacitor C
The outputs of the differential circuits of the fourth and fifth coils, which are amplified by 4, are rectified by the diode D3 and the capacitor C5
Will be charged. Then, the charging voltage of the capacitor C5 becomes
The input voltage value that can turn on the switching element Tr2, the Zener voltage of the Zener diode ZD1, and the resistance R
When it exceeds the sum of the voltage drop of 7 and the switching element Tr
2 is turned on, and the charge of the capacitor C6 connected via the resistor R6 is extracted. Then, the capacitor C
The transistor Tr1 cannot be turned on by the integration operation of 6, and the intermittent oscillation of the switching element FET1 can be stopped to allow continuous oscillation.

Therefore, when it is necessary to arrange the non-contact power receiving device 2 so as to face the non-contact power feeding device 1 so as to transfer power, the non-contact power receiving device 2 generally faces the non-contact power feeding device 2. The arrangement may be detected on the non-contact power receiving device 2 side, and the detection may be transmitted to the non-contact power feeding device 1 by a signal unique to the non-contact power feeding device 1 to continuously oscillate.

Here, in the structure and specifications of the detachable / attachable transformer to be used, the signal generator 24 is configured to resonate at a frequency (third harmonic component) three times the oscillation frequency of the high frequency inverter circuit 11. If the third coil L3 of the signal generator 24 detects the magnetic flux generated by the first coil L1, the third coil L3 and the resonance capacitor C8 are used as the excitation source to generate the third magnetic flux. Coil of
By the harmonic resonance circuit of 3 and the resonance capacitor C8,
The output amplitude of the signal generator 24 can be increased. And
The third coil L3 is excited by a resonance current having a frequency of the third harmonic component, and the magnetic flux is detected by the input signal coil Ls, and a large output voltage is generated to turn on the switching element Tr2 for switching oscillation. As a result, the high frequency inverter circuit 11 can be continuously oscillated.

Then, the signal receiving circuit 12 which operates as a differential resonance circuit composed of the fourth coil L4, the fifth coil L5 and the resonance capacitor C4 is set to the third order in the same manner as when the signal generator 24 is set. If the output amplitude is set to resonate with the frequency of the harmonic component, the signal can be detected more reliably.

The specific operation of this signal detection operation will be described below. When the non-contact power feeding device 1 is independent, the input signal coil Ls of the signal receiving circuit 12 detects the information on the magnetic flux and the magnetic field on the primary side. If the high frequency inverter circuit 11 is a voltage resonance type inverter circuit, the first coil L1
The voltage and the current of are substantially sinusoidal. Therefore,
The third harmonic component is small, the signal receiving circuit 12 is zero,
Or it outputs a low voltage. If the third harmonic component is large, the signal receiving circuit 12 may be set to reduce the output voltage. Therefore, the switching element Tr2 remains off, and the high frequency inverter circuit 11 continues intermittent oscillation.

Next, in the case where the non-contact power receiving device 2 is arranged so as to face the non-contact power feeding device 1 and needs power feeding,
The magnetic flux generated in the first coil L1 during the oscillation period of the intermittent oscillation also interlinks with the third coil L3 of the signal generator 24, and the interleaved alternating magnetic flux generates an induced voltage having the oscillation frequency of the high frequency inverter circuit 11. It is generated in the third coil L3 and the induced voltage causes the third coil L3 and the resonance capacitor C8 to perform series resonance operation. Since the series resonance frequency at this time is set to three times the oscillation frequency (fundamental wave), that is, the frequency of the third harmonic component, the third coil L
A large AC voltage having the frequency of the third harmonic component is generated in 3, and an AC current having the frequency of the third harmonic component is caused to flow in the third coil L3.

Therefore, the AC voltage having the frequency of the third-order harmonic component is induced in the fourth coil L4 arranged so as to face the third coil L3, and the signal receiving circuit 12 causes the third-order harmonic wave to occur. A voltage of large amplitude having a component frequency is output, and the voltage rectified and smoothed by the diode D3 and the capacitor C5 turns on the switching element Tr2 to switch the high frequency inverter circuit 11 from intermittent oscillation to continuous oscillation operation.

Further, when the non-contact power receiving device 2 is generally arranged opposite to the non-contact power feeding device 1 and it is necessary to stop the power feeding, the secondary side control circuit 23 turns on the auxiliary switching element Tr3, If both ends of the signal generator 24 are short-circuited via the diode D5, the harmonic resonance function is lost, and the voltage of the frequency of the third harmonic component generated at both ends of the third coil L3 becomes zero or reduced, The output of the signal receiving circuit 12 also becomes zero or a low voltage, the voltage rectified and smoothed by the diode D3 and the capacitor C5 turns off the switching element Tr2, and the high frequency inverter circuit 11 becomes intermittent oscillation. This auxiliary switching element Tr
It is not necessary to completely perform the short circuit by 3, and periodic short circuits are sufficiently effective. Further, opening a part of the circuit of the signal generating device 24 so that no current flows without short-circuiting both ends of the signal generating device 24 is also one of the methods for reducing or eliminating the harmonic resonance function. In the present embodiment, since the auxiliary switching element Tr3 is short-circuited via the diode D5, only one direction of the alternating current is short-circuited. However, such a short-circuiting in only one direction reduces the third harmonic component. The effect is sufficient.

Next, FIG. 5 shows a side sectional view of a structure in which the non-contact power receiving device 2 is generally opposed to the non-contact power feeding device 1 and has a transformer structure which can be detached and attached. This separable / detachable transformer is provided with first and second cores 14 and 25 made of a magnetic material having a U-shaped cross section in order to reduce the magnetic resistance, and the first coil L1 is the first core 14 The third and fourth coils L3 and L4 are wound between the protrusions 14a and 14b provided at both ends of the first coil L1.
Is sandwiched in the axial direction (symmetrically with respect to the axial direction of the first coil L1), and is wound between the protrusions 14a and 14b.
6 is axially sandwiched between the first coil L1 and the fifth coil L5 and wound between the protrusions 14a and 14b. Second
The coil L2 is a protrusion 25 provided at both ends of the second core 25.
The third coil L3 is wound between a and 25b, and
The second portion is provided at a position facing the fourth coil L4 between a and 25b.
Is wound separately from the coil L2 in the axial direction.

As described above, the feedback coil L for self-excited oscillation
6 is arranged in the vicinity of the first coil L1 so that the magnetic fluxes generated by the first coil L1 interlink, and the fourth and fifth coils L4, L5 forming the input signal coil Ls are The first coil L1 is arranged apart from the first coil L1 so that the magnetic flux generated by the first coil L1 is relatively loosely coupled.

The point here is that the fourth and fifth coils L4 and L5 are arranged so as not to be strongly magnetically coupled to the first coil L1. The reason is that the signal received by the fourth coil L4 from the third coil L3 must be valid and output large.
If the fourth and fifth coils L4 and L5 and the first coil L1
If and are magnetically tightly coupled, even if the magnetic flux signal generated by the third coil L3 is received, the fourth and fifth coils L3
This is because most of the output changes of 4 and L5 are governed by the magnetic flux changes generated by the first coil L1.

The fourth and fifth coils L4 and L5 are differentially connected, and the difference between the change in the detected voltage at the fourth coil L4 and the change in the detected voltage at the fifth coil L5 is calculated. It is output, and the amplification effect of the output is greatly shown. That is, if the induced voltages of the fourth and fifth coils L4 and L5 change in the same manner, there is no effect, and it is necessary to change the detection voltage of only one coil. Therefore, the differentially connected fourth and fifth coils L4 and L5 may be provided with a magnetic coupling difference with respect to the third coil L3.
Any one of the coils L4 and L5 and the third coil
The coil L3 and the third coil L3 may be arranged close to each other so that the magnetic coupling with the coil L3 may be dense, and the magnetic coupling between the other coil and the third coil L3 may be arranged sparsely. In this embodiment,
The magnetic coupling between the fourth coil L4 and the third coil L3 is tight, and the third coil L3 is arranged at a position facing the fourth coil L4.

Most of the magnetic flux 100 generated by the third coil L3 at this time is linked to the fourth coil L4, and few is linked to the fifth coil L5. In reality, the magnetic flux 100 generated by the third coil L3 is equal to the first coil L1.
Will be superposed on the magnetic flux generated by the first coil L1 and the magnetic flux generated by the current flowing through the second coil L2.
The influence of the magnetic flux generated by 2 is such that the outputs of the differentially connected fourth and fifth coils L4, L5 cancel each other out, and are not output from the input signal coil Ls.

However, a large amount of change in the magnetic flux generated by the third coil L3 interlinks only with the fourth coil L4, and a large output can be generated from the input signal coil Ls. Moreover, in the present embodiment, since the magnetic flux generated by the third coil L3 is not the oscillation frequency of the high frequency inverter circuit 11 but the frequency of the third harmonic component, the influence of the current of the first coil L1 and the The influence of the currents of the other coils can be further reduced.

The third coil L3 is the second coil L.
2 is easily affected by the magnetic flux due to the current of No. 2, but the second coil L2 and the third coil L3 are loosely coupled, so that the harmonic component of the harmonic component is not affected by the current of the second coil L2. Only magnetic flux of frequency can be generated.

Next, FIG. 6 shows a side sectional view of the primary side of the detachable detachable transformer in the case where the non-contact power feeding device 1 is alone. The first coil L1 generates a magnetic flux 101. . What is important here is that since the fourth and fifth coils L4 and L5 are separately wound around the first coil L1 symmetrically in the axial direction, the coil current IL of the first coil L1 is
The change in the interlinkage magnetic flux due to the magnetic flux 101 generated by 1 is the same for both the fourth and fifth coils L4 and L5, and the differential output can be zero or a small value.

In the present embodiment, the signal generator 24 generates a magnetic flux having a frequency of the third harmonic of the oscillation frequency of the high frequency inverter circuit 11, but a waveform having distortion is generated with respect to the fundamental wave. Therefore, the same effect can be obtained by using any of the harmonics. In particular, as in this embodiment, the waveform is close to alternating current,
When the DC component is small, odd harmonics are dominant, and these odd harmonics can be used.

By the way, in the case where the non-contact power receiving device 2 is generally arranged opposite to the non-contact power feeding device 1 and the power feeding is rejected, the signal generating device 24 is directly controlled in the non-contact power feeding system shown in FIG. The high-frequency inverter circuit 11 is intermittently oscillated, but a series circuit of a diode D8 and an auxiliary switching element Tr5 is connected between the output terminals of the second coil L2 as in the contactless power feeding system shown in FIG. Auxiliary switching element Tr by the signal from the side control circuit 23
By turning on 5, the high frequency inverter circuit 11 can be made to oscillate intermittently even if the output terminals of the second coil L2 are short-circuited. Further, as in the non-contact power feeding system shown in FIG. 8, the non-contact power receiving device 2 is provided with the auxiliary coil L7 and the auxiliary switching element Tr6 connected between both ends of the auxiliary coil L7, and a signal from the secondary side control circuit 23 is used. Even if the output terminals of the auxiliary coil L7 are short-circuited by turning on the auxiliary switching element Tr6, the high frequency inverter circuit 11 can be made to oscillate intermittently. This has the effect of short-circuiting the second coil L2 and the auxiliary coil L7 so as to cancel the magnetic flux generated by the first coil L1 and weaken the magnetic flux, so that the third coil L3 is linked to the third coil L3 as an excitation source. The output of the signal generator 24 can be reduced by weakening the magnetic flux of the intersecting first coil L1.

Further, as shown in FIG. 9, the third coil L
Even if a series circuit of the auxiliary switch S3 and the capacitor C10 is connected between both ends of 3, the output of the signal generator 24 can be controlled. This is because when the auxiliary switch S3 is turned on, the capacitor C10 is connected in parallel to the resonance capacitor C8, and the harmonic resonance frequency can be greatly changed, and the resonance frequency deviates from the resonance frequency set in the signal receiving circuit 12. Then, the output of the signal receiving circuit 12 changes. Similarly, the output of the signal generator 24 can be controlled by providing a capacitor in series or in parallel with a switching element for controlling another coil to control the output.

As described above, the contactless power supply system of the present embodiment uses the signal having the same frequency as the harmonic frequency of the power frequency to identify the power supply status and perform the power supply control, whereby the circuit configuration and the transformer structure are realized. Can be simplified, and the size of the entire system can be reduced and the cost can be reduced.

In the contactless power feeding system shown in FIGS. 1 and 7 to 9, the signal receiving circuit 12 includes the third and fourth coils L.
Although a differential resonance circuit of L3 and L4 and the resonance capacitor C4 is used, the feature of the present invention is that the signal generator 24 generates a magnetic flux of a specific harmonic frequency, and the signal receiving circuit 12 generates the magnetic flux. Since it is for detection, the signal receiving circuit 12 may have a filter function of separating a signal of a specific harmonic frequency from the signal detected by the input signal coil Ls.

(Second Embodiment) In the first embodiment, the load is a constant voltage load such as the secondary battery 22, but there are various kinds of loads such as a constant voltage load and a resistance load. Further, a rectifying circuit and a smoothing circuit are required to convert alternating current into direct current and supply it to the load, and in the first embodiment, the circuit on the secondary side is composed of a half-wave rectifying circuit. The rectification / smoothing method and the type of load are determined by the application purpose of the contactless power supply system. In portable electronic devices such as electric toothbrushes and electric shavers, a secondary battery is used as the load, and the rectifier circuit is low-cost half A rectifier circuit is often used. In the case of having such a secondary side circuit and a load, for example, the second coil L2 may be provided without providing the non-contact power receiving device 2 with a circuit for generating a magnetic flux of a harmonic frequency like the signal generating device 24. If many harmonic components are included in the waveform of the current of, the information is input to the input signal coil Ls.
It can be detected with. FIG. 10 shows the second embodiment.
Is a waveform of the voltage Vl2 across the coil L2, and the voltage V10 during the period when the diode D4 for half-wave rectification is conducting is 2
It is approximately equal to the sum of the secondary battery 22 and the voltage drop of the diode D4.

Further, the first coil L1 and the second coil L
Since it is loosely coupled with 2, as shown in the equivalent circuit of the secondary side circuit in FIG. 11, the leakage inductance La equivalent to the secondary side cannot be ignored, and the voltage source induced in the second coil L2. AC1 is connected to the series circuit of the diode D4 and the secondary battery 22 via the inductance La inserted in series. In such a circuit, even if the induced voltage source AC1 is a sine wave, the voltage across the second coil L2 is as shown in FIG.
The waveform is far from the sine wave like 0, and the period T0 is about three times as long as the period T1 in which the sine wave changes. This indicates that the voltage V12 includes many harmonic components (third harmonics) that are three times higher than the fundamental wave.

If the voltage waveform of the second coil L2 is as shown in FIG. 10, the magnetic flux component generated by the coil current of the second coil L2 has a strong influence on the entire detachable transformer section, so that the signal reception If the circuit 12 selects and amplifies the frequency of the third harmonic, the contactless power receiver 1 and the contactless power receiver 2 are generally arranged to face each other, and the operation of the high frequency inverter circuit 11 is continuously oscillated from intermittent oscillation. You can switch to. At this time, as in the first embodiment, the signal generator in which the third coil L3 and the resonance capacitor C8 are set so as to resonate at a frequency (third harmonic component) three times the oscillation frequency of the high frequency inverter circuit 11. The combination of 24 is more effective. The second shown in FIG.
Since the voltage waveform V12 of the coil L2 changes depending on the rectification condition, the load condition, and the like, not only the third harmonic, but the harmonic most included in the voltage waveform at that time may be used.

Next, referring to FIG. 12, the voltage of the second coil L2
FIG. 2 is a side sectional view of a detachable and detachable transformer structure that effectively extracts harmonic components from a current waveform. This detachable and attachable transformer is composed of a magnetic body having a U-shaped cross section in order to reduce magnetic resistance. The second coil 14 and 25 are provided, and the first coil L1 is wound between the protrusions 14a and 14b provided at both ends of the first core 14, and the third and fourth coils L3 and L4 are The first coil L1 is sandwiched in the axial direction (first
Of the coil L1), and the protrusions 14a and 14b
The feedback coil L6 is wound between the first coil L1 and the fifth coil L5 and is axially sandwiched between the protrusions 14a and 14a.
It is wound between b. The second coil L2 has a protrusion 25a between the protrusions 25a and 25b provided at both ends of the second core 25.
It is biased toward the side and wound.

The point here is that the fourth and fourth differential connections are made.
The fifth coils L4 and L5 are magnetically loosely coupled to the first coil L1, and the degree of magnetic coupling between the second coil L2 and the fourth coil L4 is such that the second coil L2 and the fifth coil L5. It is configured to be larger than the degree of magnetic coupling with.

(Embodiment 3) The contactless power supply system of this embodiment shown in FIG. 13 is substantially the same as the contactless power supply system shown in FIG. 2 of Embodiment 1, but the configuration of the signal generator 24 is different. The choke coil L7 is connected in series to the third coil L3, and the third coil L3 and the choke coil L7 are connected.
A resonance capacitor C8 is connected in parallel to a series circuit of

In the present embodiment as described above, the inductance value is increased by connecting the choke coil L7 in series to the third coil L3, and the number of turns of the third coil L3 cannot be increased due to space limitations and the like. In this case, since the inductance value is small, the resonance current becomes too large, and the heat loss may not be ignored. In such a case, if a choke coil L7 having a large inductance value is connected in series to the third coil L3 to form a resonance circuit, the resonance current can be reduced.

In the first, second and third embodiments, "oscillation stoppage or suppression control for energy saving control and measures against overheating of foreign metal particles when the power supply side is independent" and "when the correct load is mounted" are used. It is intended for three controls, "continuous power supply control" and "power transfer control based on demand from load side". However, "oscillation for energy saving control and measures against overheating of foreign metal particles when power supply side is independent" It can also be applied to a case where only two controls, "stop or suppression control" and "continuous power feeding control when a correct load is attached" are targeted.

[0088]

According to the invention of claim 1, a high frequency inverter circuit for outputting high frequency power, an inverter control circuit for controlling the high frequency inverter circuit, and high frequency power supplied from the high frequency inverter circuit are supplied by magnetic coupling. A contactless power supply device comprising: a first coil for performing; and a signal receiving circuit having an input signal coil, wherein the inverter control circuit controls the high frequency inverter circuit based on a signal detected by the input signal coil, A second coil which is arranged to face the first coil and receives power by magnetic coupling; a power conversion circuit for converting the output of the second coil into a predetermined electric energy; and a harmonic of the oscillation frequency of the high frequency inverter circuit. A signal generator that generates a signal having a frequency of a wave component, and a secondary side that controls the signal generated by the signal generator A non-contact power receiving device having a control circuit and a load supplied with electric energy from the power conversion circuit, and the first coil and the second coil have a transformer structure in which they can be detached from each other. Since the input signal coil outputs a signal detecting the presence or absence of the non-contact power receiving device and a signal detecting the signal generated by the signal generating device, a signal having the same frequency as the harmonic frequency of the power frequency is used. By controlling the power supply by identifying the power supply status with the power supply, the circuit configuration and transformer structure are simplified,
It is possible to reduce the size of the entire system and reduce the cost. Therefore, it is possible to identify the situation on the power receiving side and perform power supply control, and it is possible to provide a non-contact power transmission device having a simple structure.

According to a second aspect of the present invention, in the first aspect, the signal generating device is a resonance circuit including a third coil and a capacitor, the resonance circuit having a resonance frequency of a frequency of the harmonic component. When the non-contact power receiving device is generally arranged opposite to the contact power feeding device, it is extracted from the magnetic field, magnetic flux in the non-contact power feeding device and the non-contact power receiving device, or the voltage or current information in the non-contact power receiving device. A signal of the frequency of the harmonic component is generated, the input signal coil detects the signal of the frequency of the harmonic component, and the inverter control circuit operates the high frequency inverter circuit based on the signal detected by the input signal coil. Since the power is controlled from the contactless power feeder to the contactless power receiver, a resonance circuit is used in the signal generator to output a signal of a harmonic component frequency. There is an effect that it is possible to live.

According to a third aspect of the present invention, in the first or second aspect, since the frequency of the harmonic component is the frequency of the harmonic component that is an odd multiple of the oscillation frequency of the high frequency inverter circuit, it is close to alternating current and A device that generates a waveform having a small component has an effect that it can easily generate a signal having a frequency of a harmonic component.

According to a fourth aspect of the present invention, in the third aspect, since the odd harmonic component is the third harmonic component,
The configuration including the circuit for half-wave rectifying the output of the second coil and the constant voltage load has an effect that a signal having a frequency of a harmonic component can be easily generated.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the power conversion circuit includes a circuit for half-wave rectifying the output of the second coil, so that the cost can be reduced. effective.

In a sixth aspect of the present invention, the signal receiving circuit according to any one of the first to fifth aspects includes a resonance capacitor connected to the input signal coil, and resonates at a frequency of the harmonic component, so that a reliable There is an effect that signal detection can be performed.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the input signal coil is a fourth differential connection type.
Since the first coil and the fifth coil are included, there is an effect that the signals detected by the fourth coil and the fifth coil can be differentially output to be increased.

According to an eighth aspect of the present invention, in any one of the first to seventh aspects, in the case where the non-contact power receiving device is generally opposed to the non-contact power feeding device and the non-contact power receiving device requests power feeding. Since the output of the signal generator becomes large, the situation on the power receiving side can be identified.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects, in the case where the non-contact power receiving device is generally arranged opposite to the non-contact power receiving device and the non-contact power receiving device rejects power feeding. Since the secondary side control circuit reduces the output of the signal generator, it has the same effect as that of the eighth aspect.

According to a tenth aspect of the present invention, in any one of the first to ninth aspects, when the non-contact power feeding device is present independently, the high frequency inverter circuit performs intermittent oscillation, so that energy saving and metal foreign matter can be prevented. This has the effect of being able to take measures against overheating.

According to an eleventh aspect of the present invention, in the high-frequency inverter circuit according to any one of the second to tenth aspects, a switching element for oscillation and a switching element for self-excitation control for connecting a control end of the oscillation switching element to a ground level. And performing a self-excited oscillation, wherein the inverter control circuit intermittently stops the oscillation of the self-excitation control switching element to intermittently stop the oscillation operation of the oscillation switching element, and the forced stop circuit, An oscillation switching switching element that stops the intermittent stop operation of the forced stop circuit by turning on at the output of the input signal coil, and when the non-contact power supply device is independent, the output voltage of the input signal coil is The switching element for oscillation switching is maintained at a voltage at which it is turned off, and the forced stop circuit operates to cause the oscillation switch for oscillation. When the oscillation operation of the contacting element is controlled to intermittent oscillation, the non-contact power receiving device is generally arranged in opposition to the non-contact power feeding device, and when the non-contact power receiving device requests power feeding, the signal generating device is the The magnetic field and magnetic flux in the non-contact power feeding device and the non-contact power receiving device, which are generated during the period in which the oscillation operation of the oscillation switching element is intermittent oscillation.
Alternatively, the third coil is excited by a signal of the frequency of the harmonic component extracted from the voltage or current information in the non-contact power receiving device, and the third coil is roughly arranged to face the third coil.
The output voltage of the input signal coil for detecting the magnetic flux generated in the third coil becomes a voltage at which the oscillation switching switching element is turned on, and the forced stop circuit stops the operation to oscillate the oscillation switching element. When the operation is controlled to continuous oscillation, the non-contact power receiving device is generally arranged in opposition to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator is configured to suppress the harmonic component. The frequency signal is reduced to suppress the excitation of the third coil, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to cause the oscillation. Since the oscillating operation of the switching element is controlled to intermittent oscillation, a self-excited control inverter is used in the non-contact power feeding device to switch between continuous oscillation and intermittent oscillation according to the identified situation on the power receiving side. There is an effect that can be obtained.

According to a twelfth aspect of the present invention, in any one of the second to eleventh aspects, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of a resonant circuit including a third coil and a capacitor. When the non-contact power receiving device is generally arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element. Changing at least one of the frequency, the amplitude and the waveform of the signal generated by the resonance circuit of the signal generator with respect to the frequency, the amplitude and the waveform when the power supply is required,
The input signal coil detects a signal generated by the signal generator, the inverter control circuit controls the high frequency inverter circuit based on the signal detected by the input signal coil, and causes the non-contact power feeding device to operate the non-contact power supply device. Since the power supply to the contact power receiving device is reduced, it is possible to change the signal generated by the signal generating device by turning on and off the auxiliary switching element to identify the condition of the power receiving side and perform power supply control. effective.

According to a thirteenth aspect of the present invention, in any one of the second to eleventh aspects, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generating device. When the non-contact power receiving device is generally arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element to operate the signal. At least one of the frequency, the amplitude, and the waveform of the signal generated by the resonance circuit of the generator is changed with respect to the frequency, the amplitude, and the waveform when the power supply is required, and the input signal coil causes the signal generator to change. Is detected, the inverter control circuit controls the high-frequency inverter circuit based on the signal detected by the input signal coil to perform the contactless power feeding. Since reducing placed et the power supply to the non-contact power receiving apparatus, the same effects as claim 12.

According to a fourteenth aspect of the present invention, in the non-contact power receiving device according to the thirteenth aspect, the auxiliary coil in which at least a part of the magnetic flux generated by the first coil links with the auxiliary coil is short-circuited or opened. An auxiliary switching element, the non-contact power receiving device is generally arranged opposite to the non-contact power feeding device, and when the non-contact power receiving device rejects power feeding, the secondary side control circuit is configured to perform the auxiliary switching. 13. The element is operated to reduce at least one of the frequency and the amplitude of the signal generated by the resonance circuit of the signal generator with respect to the frequency and the amplitude when the power supply is required. Produce an effect.

According to a fifteenth aspect of the present invention, in the twelfth aspect, the signal generator comprises a resonance circuit in which a third coil and a capacitor are connected in parallel, and a diode and an auxiliary switching element are provided between both ends of the parallel circuit. When the non-contact power receiving device is arranged to face the non-contact power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit controls the auxiliary switching element. Since the third coil is turned on to suppress the excitation of the third coil, the same effect as in claim 12 is obtained.

According to a sixteenth aspect of the present invention, in the thirteenth aspect, the non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, and the non-contact power feeding device is provided with the non-contact power receiving device. , The secondary side control circuit operates the auxiliary switching element when the contactless power receiving device is arranged to face each other and rejects power supply,
The frequency of the signal generated by the resonant circuit of the signal generator,
Since at least one of the amplitudes is made smaller than the frequency and the amplitude when the power supply is required, the same effect as that of the twelfth aspect can be obtained.

The invention of claim 17 is based on claims 12 to 16.
In either case, since the auxiliary switching element is an element that conducts in one direction, there is an effect that the auxiliary switching element can be easily selected.

The invention of claim 18 relates to claims 12 to 17.
In any one of the above, since the auxiliary switching element is provided with a capacitor connected in series, by turning on / off the auxiliary switching element, the frequency of the signal generated by the signal generator is greatly changed to determine the situation on the power receiving side. The effect is that it can be performed more reliably.

The invention of claim 19 is based on claims 12 to 17.
In any one of the above, since a capacitor connected in parallel to the auxiliary switching element is provided, the same effect as in claim 18 is achieved.

According to the twentieth aspect of the invention, in any one of the first to nineteenth aspects, the magnetic coupling between the second coil and the third coil is loose coupling, so that it is affected by the coil current of the second coil. Instead, the third coil has an effect that it can generate a magnetic flux.

According to a twenty-first aspect of the present invention, in any one of the first to twentieth aspects, a filter for detecting the same frequency band as the frequency of the harmonic component is provided at the output section of the input signal coil, so that a reliable signal can be obtained. There is an effect that detection can be performed. .

In a twenty-second aspect of the present invention based on any one of the first to twenty-first aspects, the high-frequency inverter circuit applies a sinusoidal alternating voltage across the first coil.
There is an effect that a voltage resonance type inverter circuit can be used as the high frequency inverter circuit.

In a twenty-third aspect of the present invention based on any one of the first to twenty-second aspects, the high frequency inverter circuit includes an oscillation switching element and a resonance capacitor connected in parallel to the oscillation switching element or the first coil. Since it is a single voltage resonance inverter, there is an effect that a sinusoidal alternating voltage can be applied across the first coil.

According to a twenty-fourth aspect of the present invention, in any one of the seventh to twenty-third aspects, the magnetic coupling between the differentially connected fourth and fifth coils constituting the input signal coil and the first coil is loose coupling. And the degree of magnetic coupling between any one of the fourth coil and the fifth coil and the third coil is the same as that between the other of the fourth coil and the fifth coil and the third coil. Since the magnetic coupling degree is larger than the magnetic coupling degree, the differential output between the fourth coil and the fifth coil can be obtained.

According to a twenty-fifth aspect of the present invention, in the twenty-fourth aspect, the fourth and fifth coils are arranged symmetrically with respect to the first coil, and the third coil includes the fourth coil and the fifth coil. Since it is arranged so as to face either one of the coils, it is possible to reduce the influence of the magnetic flux generated in the first coil on the differential output between the fourth coil and the fifth coil, and There is an effect that the degree of magnetic coupling between the third coil and the fourth coil and the degree of magnetic coupling between the third coil and the fifth coil can be made different.

The invention of claim 26 is the same as that of claim 1
When power is being supplied from the non-contact power feeding device to the non-contact power receiving device, the voltage across the second coil and the coil current have distorted waveforms, and the signal generating device causes the voltage across the second coil and the coil Since the signal is generated by using the harmonic component included in the current as the generation source, there is an effect that the signal generator can be easily configured.

According to a twenty-seventh aspect of the present invention, in the twenty-sixth aspect, a fourth differential connection type circuit that constitutes the input signal coil is provided.
The magnetic coupling between the fifth coil and the first coil is loose coupling, and the degree of magnetic coupling between any one of the fourth coil and the fifth coil and the second coil is the fourth coil. And the fifth
Since the degree of magnetic coupling between one of the other coils and the second coil is larger than that of the other coil, it is possible to obtain a differential output by the magnetic flux generated by the second coil.

In a twenty-eighth aspect of the present invention based on any one of the first to twenty-seventh aspects, the signal generating device is a signal generating means by a resonance circuit of a third coil and a capacitor having a resonance frequency of the frequency of the harmonic component. And a signal generating means for generating a signal whose source is a harmonic component included in the coil current and the voltage across the second coil, so that the signal generating device outputs a signal that is easier to determine the situation on the power receiving side. There is an effect that can occur in.

The invention of claim 29 is based on claims 1 to 25,
In any one of 28, since the signal generator includes an inductor connected in series to the third coil, there is an effect that loss due to current can be reduced even when the inductance of the third coil is small.

[Brief description of drawings]

FIG. 1 is a diagram showing a block configuration according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a first circuit configuration of the above.

FIG. 3 is a diagram showing a waveform of each part from the startup to continuous oscillation in the above.

FIG. 4 is a diagram showing a waveform of each part from the above startup to intermittent oscillation.

FIG. 5 is a side sectional view showing a structural example of the above detachable detachable transformer.

FIG. 6 is a side sectional view showing a primary side of a structural example of the above detachable detachable transformer.

FIG. 7 is a diagram showing a second circuit configuration of the above.

FIG. 8 is a diagram showing a third circuit configuration of the above.

FIG. 9 is a diagram showing a fourth circuit configuration of the above.

FIG. 10 is a diagram showing a voltage waveform across a second coil according to the second embodiment of the present invention.

FIG. 11 is a diagram showing an equivalent circuit on the secondary side of the above.

FIG. 12 is a side sectional view showing a structural example of the above detachable detachable transformer.

FIG. 13 is a diagram showing a circuit configuration according to a third embodiment of the present invention.

[Explanation of symbols]

1 Non-contact power supply device 2 Non-contact power receiving device 11 High frequency inverter circuit 12 Signal receiving circuit 13 Inverter control circuit 21 Power conversion circuit 23 Secondary side control circuit 24 signal generator 30 load L1 to L5 first to fifth coils Ls input signal coil C4, C8 resonance capacitor S2 switch

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshiki Katsura             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company (72) Inventor Mikihiro Yamashita             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 5H006 AA04 CA02 CA07 CA12 CB03                       CC02 DC05 GA01                 5H115 PC06 PG04 PI02 PI21 PI29                       PO01 PO07 PO16 PU01 QE12                       SE06                 5H730 AA12 BB43 BB52 BB77 BB80                       DD04 EE02 EE07 FD24 FF01                       FG07 FG09 XC02 ZZ11 ZZ16

Claims (29)

[Claims] 1. A high-frequency inverter circuit that outputs high-frequency power, an inverter control circuit that controls the high-frequency inverter circuit, and a first coil that is supplied with high-frequency power from the high-frequency inverter circuit and that supplies power by magnetic coupling. A signal receiving circuit having an input signal coil,
A contactless power supply device in which the inverter control circuit controls the high-frequency inverter circuit based on a signal detected by the input signal coil; and a second coil which is arranged to face the first coil and receives power by magnetic coupling. A power conversion circuit for converting the output of the second coil into a predetermined electric energy, a signal generator for generating a signal having a frequency of a harmonic component of the oscillation frequency of the high frequency inverter circuit, and the signal generator. A non-contact power receiving device that includes a secondary side control circuit that controls a generated signal and a load that is supplied with electric energy from the power conversion circuit,
The first coil and the second coil have a transformer structure that is detachable from each other, and the input signal coil detects a signal for detecting the presence or absence of the non-contact power receiving device and a signal generated by the signal generating device. A contactless power supply system, which outputs a detected signal. 2. The signal generating device is a resonance circuit including a third coil and a capacitor, and having a resonance frequency of the frequency of the harmonic component, wherein the non-contact power feeding device includes the non-contact power receiving device. Generally, in the case where they are arranged to face each other, the magnetic field and magnetic flux in the non-contact power feeding device and the non-contact power receiving device,
Alternatively, by generating a signal of the frequency of the harmonic component extracted from the voltage or current information in the non-contact power receiving device, the input signal coil detects the signal of the frequency of the harmonic component, the inverter control circuit is the The non-contact power feeding system according to claim 1, wherein the high frequency inverter circuit is controlled based on a signal detected by an input signal coil to control power feeding from the non-contact power feeding device to the non-contact power receiving device. . 3. The contactless power feeding system according to claim 1, wherein the frequency of the harmonic component is a frequency of a harmonic component that is an odd multiple of the oscillation frequency of the high frequency inverter circuit. 4. The contactless power feeding system according to claim 3, wherein the odd harmonic component is a third harmonic component. 5. The contactless power supply system according to claim 1, wherein the power conversion circuit includes a circuit that half-wave rectifies the output of the second coil. 6. The contactless power supply system according to claim 1, wherein the signal receiving circuit includes a resonance capacitor connected to the input signal coil, and resonates at a frequency of the harmonic component. . 7. The non-contact power feeding system according to claim 1, wherein the input signal coil includes a fourth coil and a fifth coil which are differentially connected. 8. The non-contact power receiving device is generally arranged opposite to the non-contact power feeding device, and when the non-contact power receiving device requests power feeding, the output of the signal generating device increases. The contactless power supply system according to claim 1. 9. The secondary-side control circuit outputs the signal from the signal generating device when the non-contact power receiving device is generally arranged opposite to the non-contact power feeding device and the non-contact power receiving device rejects power feeding. 9. The contactless power feeding system according to claim 1, wherein the power consumption is reduced. 10. The contactless power supply system according to claim 1, wherein the high-frequency inverter circuit performs intermittent oscillation when the contactless power supply device is present alone. 11. The inverter control circuit, wherein the high-frequency inverter circuit includes an oscillation switching element and a self-exciting control switching element that connects a control end of the oscillation switching element to a ground level to perform self-excited oscillation. Is a forced stop circuit for intermittently stopping the oscillation of the switching element for oscillation by intermittently stopping the oscillation of the switching element for self-excitation control, and the forced stop circuit for turning on the output of the input signal coil. An oscillation switching switching element for stopping the intermittent stop operation is provided, and when the non-contact power feeding device is independent, the output voltage of the input signal coil is maintained at a voltage at which the oscillation switching switching element is turned off. The forced stop circuit operates to control the oscillation operation of the oscillation switching element to intermittent oscillation, and When the non-contact power receiving device is generally arranged opposite to the tactile power feeding device and the non-contact power receiving device requests power feeding, the signal generating device is configured such that the oscillation operation of the oscillation switching element is in the intermittent oscillation period. The generated magnetic field, magnetic flux in the non-contact power feeding device and the non-contact power receiving device,
Alternatively, the third coil is excited by a signal of the frequency of the harmonic component extracted from the voltage or current information in the non-contact power receiving device, and the third coil is roughly arranged to face the third coil.
The output voltage of the input signal coil for detecting the magnetic flux generated in the third coil becomes a voltage at which the oscillation switching switching element is turned on, and the forced stop circuit stops the operation to oscillate the oscillation switching element. When the operation is controlled to continuous oscillation, the non-contact power receiving device is generally arranged in opposition to the non-contact power feeding device, and the non-contact power receiving device rejects power feeding, the signal generator is configured to suppress the harmonic component. The frequency signal is reduced to suppress the excitation of the third coil, the output voltage of the input signal coil becomes a voltage at which the oscillation switching element is turned off, and the forced stop circuit operates to cause the oscillation. 11. The contactless power feeding system according to claim 2, wherein the oscillation operation of the switching element is controlled to be intermittent oscillation. 12. The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of a resonance circuit including a third coil and a capacitor, and the non-contact power receiving device includes the non-contact power receiving device. In general, when the contactless power receiving devices are arranged opposite to each other and the power supply is rejected, the secondary side control circuit operates the auxiliary switching element, and the frequency of the signal generated by the resonance circuit of the signal generating device. , At least one of the amplitude and the waveform is changed with respect to the frequency, the amplitude and the waveform when power is required,
The input signal coil detects a signal generated by the signal generator, the inverter control circuit controls the high frequency inverter circuit based on the signal detected by the input signal coil, and causes the non-contact power feeding device to operate the non-contact power supply device. The non-contact power feeding system according to claim 2, wherein power feeding to the contact power receiving device is reduced. 13. The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens at least a part of an internal circuit other than the signal generating device, and the non-contact power receiving device is generally opposed to the non-contact power receiving device. When arranged, when the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element to cause a frequency, an amplitude of a signal generated by the resonance circuit of the signal generating device, At least one of the waveforms is changed with respect to the frequency, the amplitude, and the waveform when power is required to be supplied, the input signal coil detects the signal generated by the signal generator, and the inverter control circuit Controlling the high-frequency inverter circuit based on the signal detected by the input signal coil to reduce power supply from the non-contact power feeding device to the non-contact power receiving device. The contactless power supply system according to any one of claims 2 to 11, which is characterized in that. 14. The non-contact power receiving device includes an auxiliary coil in which at least a part of the magnetic flux generated by the first coil interlinks, and an auxiliary switching element that short-circuits or opens the auxiliary coil. When the non-contact power receiving device is generally arranged opposite to the power feeding device and the non-contact power receiving device rejects power feeding, the secondary side control circuit operates the auxiliary switching element to cause the signal generating device. 14. The contactless power supply system according to claim 13, wherein at least one of the frequency and the amplitude of the signal generated by the resonance circuit is set smaller than the frequency and the amplitude when the power supply is required. 15. The signal generator comprises a resonance circuit in which a third coil and a capacitor are connected in parallel, and a series circuit of a diode and an auxiliary switching element is provided between both ends of the parallel circuit, and the non-contact power feeding. When the non-contact power receiving device is generally arranged opposite to the device and the non-contact power receiving device rejects power feeding, the secondary side control circuit turns on the auxiliary switching element to excite the third coil. The non-contact electric power feeding system of Claim 12 which suppresses. 16. The non-contact power receiving device includes an auxiliary switching element that short-circuits or opens the second coil, and the non-contact power receiving device is generally arranged to face the non-contact power receiving device. When the device rejects the power supply, the secondary side control circuit operates the auxiliary switching element to supply at least one of the frequency and the amplitude of the signal generated by the resonance circuit of the signal generating device. The contactless power supply system according to claim 13, wherein the frequency and the amplitude are reduced when necessary. 17. The auxiliary switching element is an element which conducts in one direction, according to claim 12.
6. The contactless power feeding system according to any one of 6 above. 18. The contactless power supply system according to claim 12, further comprising a capacitor connected in series to the auxiliary switching element. 19. The contactless power feeding system according to claim 12, further comprising a capacitor connected in parallel to the auxiliary switching element. 20. The magnetic coupling between the second coil and the third coil is loose coupling.
The contactless power supply system according to any one of the above. 21. The contactless power supply system according to claim 1, wherein a filter for detecting the same frequency band as the frequency of the harmonic component is provided at an output part of the input signal coil. 22. The contactless power supply system according to claim 1, wherein the high frequency inverter circuit applies a sinusoidal alternating voltage across the first coil. 23. The high-frequency inverter circuit is a monolithic voltage resonance inverter including an oscillation switching element and a resonance capacitor connected in parallel with the oscillation switching element or the first coil. Item 23. The contactless power feeding system according to any one of Items 1 to 22. 24. The magnetic coupling between the first coil and the differentially connected fourth and fifth coils forming the input signal coil is a loose coupling, and the magnetic coupling among the fourth coil and the fifth coil is 8. The degree of magnetic coupling between any one of the third coil and the third coil is larger than the degree of magnetic coupling between the other of the fourth coil and the fifth coil and the third coil. 24. The contactless power feeding system according to any one of 23 to 23. 25. The fourth and fifth coils are arranged symmetrically with respect to the first coil, and the third coil faces either one of the fourth coil and the fifth coil. 25. The contactless power feeding system according to claim 24, wherein the contactless power feeding system is arranged. 26. When power is being supplied from the non-contact power feeding device to the non-contact power receiving device, a voltage across the second coil,
The coil current has a distorted waveform, and the signal generator is
The non-contact power feeding system according to claim 1, wherein a signal is generated by using a harmonic component included in a voltage across the second coil and a coil current as a generation source. 27. The magnetic coupling between the first coil and the differentially connected fourth and fifth coils forming the input signal coil is a loose coupling, and the magnetic coupling among the fourth coil and the fifth coil is 27. The degree of magnetic coupling between any one of the second coil and the second coil is greater than the degree of magnetic coupling between the other of the fourth coil and the fifth coil and the second coil. The contactless power supply system described. 28. The signal generator includes a signal generating means by a resonance circuit of a third coil having a resonance frequency of the harmonic component and a capacitor, and a voltage across the second coil and a coil current. 28. The contactless power feeding system according to claim 1, further comprising a signal generating unit that generates a signal using a generated harmonic component as a generation source. 29. The contactless power supply system according to claim 1, wherein the signal generator includes an inductor connected in series with a third coil.